Clutch release mechanisms in manual transmission vehicles generally include a carrier that is moved axially toward and away from a plurality of declutching fingers of a diaphragm-type clutch. A control means, such as a fork or hydraulic cylinder, moves the carrier. A bearing device is necessary between the carrier and the declutching fingers to mate the axial motion of the carrier to the rotary motion of the declutching fingers.
While a conventional thrust bearing has been used in the past in such a clutch release mechanism, the trend today is toward the use of a radial bearing having inner and outer races with a complement of bearing balls therebetween. It is also desirable that a means for allowing the bearing to self-center relative to the clutch be provided, since the carrier itself may not always be coaxial with the clutch. One conventional and simple self-centering means may be seen in the U.S. patent to Maurice, U.S. Pat. No. 3,416,637. A resilient element, such as a Belleville washer, is compressed against a face of one of the races of the bearing to bias the other face of the race into a radial wall of the carrier and hold the race non-rotatably, but radially slidable, relative to the carrier. The other race of the bearing is free to rotate and has a contact member that is engageable with the declutching fingers as the carrier moves. The radial sliding provided by the compressed resilient element allows the bearing to move to a centered position relative to the clutch. One means of compressing the resilient element is an attachment member that is detachably joinable to the carrier so as to axially compress the resilient element between the bearing face and a radial flange of the attachment member. This also mounts the bearing to the carrier.
An example of a clutch release bearing assembly of the type referred to above may be seen in the UK patent application No. GB 2073353A. There, the clutch release bearing assembly includes a radial bearing in which the outer race is held to the carrier by an attachment member that snap fits with the carrier to axially compress a resilient washer between a radial flange of the attachment member and a face of the outer race. The inner race is engageable with the declutching fingers. However, the attachment member is separate from the bearing and must be separately handled when the bearing is mounted to the carrier. A similar design is found in the U.S. patent to Beccaris, U.S. Pat. No. 4,403,685. Not only is the attachment member a separately handled piece, but an additional cover member is necessary to fill the gap between the inner and outer races to shield the rolling elements of the bearing.